This invention relates to a method for providing a positive transmitter power switch-on in a dual-mode mobile radiotelephone having a programmable logic in the digital mode controlling the switching-on of two or more transmitting power amplifier sections.
In digital mobile radiotelephones planned to operate according to North American dual-mode standard it is required that the transmitter must be switched off during certain specified intervals when the mobile phone operates in the digital mode. The transmitter is switched on for transmission during transmission intervals. A simple on/off switching of the transmitter produces some negative effects, e.g. a very broad frequency spectrum of the transmitter in the initial transmission phase.